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1	THE USE OF TELEMETRY IN AN ELECTROMAGNETIC TEST ENVIRONMENT Papich, William J. 10 1900 (has links) International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The U.S. Army Redstone Technical Test Center (RTTC) uses telemetry as a vital part of its data acquisition and analysis for electromagnetic environmental effects developmental testing of U.S. Army weapon systems. Testing in an electromagnetic environment poses several unique challenges. These challenges have resulted in the development of highly customized telemetry and data acquisition systems. This paper discusses the design and integration of past and current telemetry needs to incorporate real-time or near real-time simulations or scene generations into the testing process. Frequency Modulation (FM) Hardware-in-the-Loop (HWIL) Radio Frequency (RF) Data Acquisition Pulse Code Modulation (PCM) Electromagnetic
2	Modelling of gyro in an IR seeker for real-time simulation / Modellering av gyro i en IR-målsökare för realtidssimulering Nordman, Thomas January 2004 (has links) <p>The target tracking system of an IR (InfraRed) guided missile is constantly subjected to disturbances due to the linear and angular motion of the missile. To diminish these LOS (Line Of Sight) disturbances the seeker of the missile can be built from a free gyroscope mounted in a very low friction suspension. The ability of the spinning gyroscope to maintain its direction relative to an inertial frame is used to stabilize the seeker LOS while tracking a target. The tracking velocity of the seeker, i.e. its angular velocity, is controlled by a feedback control unit where the signal from the IR detector is used as input. The electrical driven actuator consists of a set of coils and a magnet on the gyroscope. </p><p>The purpose of this thesis is to develop a real-time model of the seeker gyroscope in an existing IR MANPAD (MAN Portable Air Defense) missile. The aim is a model that is able to simulate the real system with consideration to the tracking velocity. The model should also be integrated into a hybrid simulator environment. </p><p>With relatively good knowledge of the system and its subsystems an initial physical modelling approach was used where elementary equations and accepted relations were assembled to describe the mechanism of the subsystems. This formed the framework of the model and gave a good foundation for further modelling. By using experimentation and more detailed system knowledge the initial approach could be developed and modified. Necessary approximations were made and unknown parameters were determined through system identification methods. The model was implemented in MATLAB Simulink. To make it suitable for real-time operation Real-Time Workshop was used. </p><p>The model design was evaluated in simulations where the tracking performance could be tested for different positions of the gyroscope. The results where satisfying and showed that the model was able to reproduce the output of the system well considering the speed of the model and the approximations made. One important reason that good results can be achieved with a relatively simple model is that the seeker is limited to small rotations. The model can be tuned to operate in a smaller range and the complexity can be kept low. A weakness of the model is that the output error increases for wide angles.</p> Reglerteknik gyroscope real-time model modelling seeker HWIL IR missile Reglerteknik Automatic control Reglerteknik
3	Modelling of gyro in an IR seeker for real-time simulation / Modellering av gyro i en IR-målsökare för realtidssimulering Nordman, Thomas January 2004 (has links) The target tracking system of an IR (InfraRed) guided missile is constantly subjected to disturbances due to the linear and angular motion of the missile. To diminish these LOS (Line Of Sight) disturbances the seeker of the missile can be built from a free gyroscope mounted in a very low friction suspension. The ability of the spinning gyroscope to maintain its direction relative to an inertial frame is used to stabilize the seeker LOS while tracking a target. The tracking velocity of the seeker, i.e. its angular velocity, is controlled by a feedback control unit where the signal from the IR detector is used as input. The electrical driven actuator consists of a set of coils and a magnet on the gyroscope. The purpose of this thesis is to develop a real-time model of the seeker gyroscope in an existing IR MANPAD (MAN Portable Air Defense) missile. The aim is a model that is able to simulate the real system with consideration to the tracking velocity. The model should also be integrated into a hybrid simulator environment. With relatively good knowledge of the system and its subsystems an initial physical modelling approach was used where elementary equations and accepted relations were assembled to describe the mechanism of the subsystems. This formed the framework of the model and gave a good foundation for further modelling. By using experimentation and more detailed system knowledge the initial approach could be developed and modified. Necessary approximations were made and unknown parameters were determined through system identification methods. The model was implemented in MATLAB Simulink. To make it suitable for real-time operation Real-Time Workshop was used. The model design was evaluated in simulations where the tracking performance could be tested for different positions of the gyroscope. The results where satisfying and showed that the model was able to reproduce the output of the system well considering the speed of the model and the approximations made. One important reason that good results can be achieved with a relatively simple model is that the seeker is limited to small rotations. The model can be tuned to operate in a smaller range and the complexity can be kept low. A weakness of the model is that the output error increases for wide angles. Reglerteknik gyroscope real-time model modelling seeker HWIL IR missile Reglerteknik Automatic control Reglerteknik
4	Hardware-in-the-Loop Simulation of Aircraft Actuator Braun, Robert January 2009 (has links) <p>Advanced computer simulations will play a more and more important role in future aircraft development and aeronautic research. Hardware-in-the-loop simulations enable examination of single components without the need of a full-scale model of the system. This project investigates the possibility of conducting hardware-in-the-loop simulations using a hydraulic test rig utilizing modern computer equipment. Controllers and models have been built in Simulink and Hopsan. Most hydraulic and mechanical components used in Hopsan have also been translated from Fortran to C and compiled into shared libraries (.dll). This provides an easy way of importing Hopsan models in LabVIEW, which is used to control the test rig. The results have been compared between Hopsan and LabVIEW, and no major differences in the results could be found. Importing Hopsan components to LabVIEW can potentially enable powerful features not available in Hopsan, such as hardware-in-the-loop simulations, multi-core processing and advanced plotting tools. It does however require fast computer systems to achieve real-time speed. The results of this project can provide interesting starting points in the development of the next generation of Hopsan.</p> Hardware-in-the-loop HWiL Hopsan LabVIEW Saab 2000 Ironbird Fortran Rudder Elevator code translation multicore multi-core real-time simulation hydraulics test rig Hardware-in-the-loop HWiL Hopsan LabVIEW Saab 2000 Ironbird Fortran Höjdroder Sidoroder kodöversättning multicore multi-core realtid simulering realtidssimulering hydraulik testrig Mechanical engineering Maskinteknik
5	Hardware-in-the-Loop Simulation of Aircraft Actuator Braun, Robert January 2009 (has links) Advanced computer simulations will play a more and more important role in future aircraft development and aeronautic research. Hardware-in-the-loop simulations enable examination of single components without the need of a full-scale model of the system. This project investigates the possibility of conducting hardware-in-the-loop simulations using a hydraulic test rig utilizing modern computer equipment. Controllers and models have been built in Simulink and Hopsan. Most hydraulic and mechanical components used in Hopsan have also been translated from Fortran to C and compiled into shared libraries (.dll). This provides an easy way of importing Hopsan models in LabVIEW, which is used to control the test rig. The results have been compared between Hopsan and LabVIEW, and no major differences in the results could be found. Importing Hopsan components to LabVIEW can potentially enable powerful features not available in Hopsan, such as hardware-in-the-loop simulations, multi-core processing and advanced plotting tools. It does however require fast computer systems to achieve real-time speed. The results of this project can provide interesting starting points in the development of the next generation of Hopsan. Hardware-in-the-loop HWiL Hopsan LabVIEW Saab 2000 Ironbird Fortran Rudder Elevator code translation multicore multi-core real-time simulation hydraulics test rig Hardware-in-the-loop HWiL Hopsan LabVIEW Saab 2000 Ironbird Fortran Höjdroder Sidoroder kodöversättning multicore multi-core realtid simulering realtidssimulering hydraulik testrig Mechanical engineering Maskinteknik
6	Simulation and Testing of Energy Efficient Hydromechanical Drivlines for Construction Equipment Larsson, Viktor, Larsson, L. Viktor January 2014 (has links) Increased oil prices and environmental issues have increased a need of loweringthe emissions from and the fuel consumption in heavy construction machines. Anatural solution to these issues is a lowered input power through downsizing ofthe engine. This implies a demand on higher transmission efficiency, in order tominimize the intrusion on vehicle performance. More specifically, alternatives tothe conventional torque converter found in heavier applications today, must beinvestigated. One important part of this is the task of controlling the transmissionwithout jeopardising the advantages associated with the torque converter, such asrobustness and controllability.In this thesis, an alternative transmission concept for a backhoe loader is investigated.The studied concept is referred to as a 2-mode Jarchow power-splittransmission, where a mechanical path is added to a hydrostatic transmission inorder to increase transmission efficiency. The concept is evaluated in computerbased simulations as well as in hardware-in-the-loop simulations, where a physicalhydrostatic transmission is exposed for the loads caused by the vehicle duringvarying conditions. The loads are in turn simulated according to developed modelsof the mechanical parts of the vehicle drive line.In total, the investigated concept can be used instead of the torque converterconcept, if the hydrostatic transmission is properly controlled. The results alsoshow that there is a high possibility that the combustion engine in the backhoeloader can be downsized from 64 kW to 55 kW, which would further increase thefuel savings and reduce the emissions. hydraulic power-split hydrostatic PST HST mechatrinics oil volvo backhoe transmission harware-in-the-loop simulation hopsan control PID feed forward HWIL fluid power Hydraulik power-split hydrostat PST HST mekatronik olja volvo backhoe transmission harware-in-the-loop simulering hopsan reglering PID framkoppling HWIL Other Mechanical Engineering Annan maskinteknik

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